1. Field of the Invention
The present invention relates to devices, systems, and processes useful as vehicle seat assemblies, and more specifically to anti-backlash mechanisms in the seat adjustment drive mechanisms of such vehicle seat assemblies.
2. Brief Description of the Related Art
Anti-backlash gear mechanisms are well known in the art to provide a useful way of reducing or eliminating gaps between the teeth of driving and driven gears. By way of example, several U.S. patents describe such anti-backlash mechanisms, including U.S. Pat. Nos.: 1,748,820, 2,092,888, 2,310,232, 2,311,902, 2,607,238, 3,365,973, 5,056,613, and 6,293,166.
A problem in current vehicle seating design is that, while seat assemblies are being constructed to be more adjustable in numerous ways, and those adjustment mechanisms are often driven by drive motors, looseness in the adjustment mechanism can arise. Regardless of the source of this looseness, e.g., by too large a manufacturing tolerance of the component pieces or wear of the interacting parts, looseness can be perceived by the vehicle user as a fault in the mechanism, and in general is preferable to avoid.
Currently, vehicle seat adjustment mechanisms often employ simple gear reductions or worm-gear mechanisms to transform the rotation of a high RPM, low torque drive motor of the seat assembly into a desired recliner, height, and/or slide motion of the power seat. Typically, tolerances are kept very tight to reduce initial looseness; however, that initial looseness is invariably present, and can become more pronounced as the assemblies components wear.
There thus remains a need in vehicle seating assemblies to reduce or eliminate gaps in the gearing of the adjustment mechanisms of the seat assemblies, and thereby reduce or eliminate looseness in these adjustment mechanisms.